function y = Diagonal_4(x)
%  Diagonal4 Function
%x0=[1,1,...,1,1] 
%fmin=n/2
%Author:shi yangyang
n=length(x);
m=n/2;
y=ones(1,m);
for i=1:1:m
    y(i)=0.5*((x(2*i-1))^2+100*(x(2*i))^2);
end
y=sum(y);
